Soap bar composition

ABSTRACT

A composition for a soap bar comprises:  
     (i) from about 0.01 to about 7% by weight of silicone;  
     (ii) from about 0.5% to about 5%, by weight of a first emollient selected from the group consisting of from polyols, selected from the group consisting of glycerin, sorbitol, and mixtures thereof;  
     (iii) about 0.1 to about 5% by weight, of a second emollient selected from the group consisting of vegetable, animal or mineral oils, free fatty acids and mixtures thereof;  
     (iv) about 60% to 90% by weight fatty acid soap;  
     wherein bar has L% light transmittance under 40%.

[0001] The present invention refers to a novel soap composition,particularly to an opaque toilet soap bar for cleansing body skin, whichhas an improved mildness.

[0002] A general problem in the formulation of soap bars has been thatof finding a balance between providing structure whilst both maintaininglathering properties and imparting beneficial mildness to the skin, at apractical overall cost.

[0003] The conventional soap making process is well documented in theliterature. Patent application WO 92/08444 discloses a skin cleansingbar, which may be soap based and contains 0.5-20% of a siliconegum/silicone fluid. Polyalkyl siloxanes are preferred. This compositionimproves skin conditioning and moisturization, and reduces bothirritation and dryness. Optional ingredients include fatty acid asplasticizer, glycerine as moisturizer and a whole range of vegetableoils as occlusive moisturizers.

[0004] Patent application EP 578,841 discloses a solid soap containing0.5-7% of a water insoluble silicone

[0005] and optional ingredients such as glycerine. This product isintended to reduce cracking and flaking of the skin and to improvemoisture retention.

[0006] Patent application GB 2,058,822 discloses a soap compositioncontaining 0.01-6% of polydiorganosiloxane of molecular weight 2000 orhigher and containing nitrogen and improves the feel of the skin afteruse.

[0007] Patent application GB 2,143,250 discloses a combination ofvegetable oil and silicone oil which is used in a personal cleansingcomposition.

[0008] Patent application WO 94/17172 (Unilever) discloses asyndet-based bar composition containing 0.1-9% of silicone and from0-25% of soap and 0-35% of free fatty acids.

[0009] Patent application JP 01/294,797 discloses mixtures of siliconeoils and optionally polyols (e.g., glycerol) which are used in soapsbased on counterions derived from weak bases.

[0010] Patent application JP 01/060,696 discloses mixtures of siliconeoils and optionally polyols (e.g., glycerol) which are used intransparent soaps.

[0011] U.S. Pat. No. 5,154,849 to Visscher teaches “mild” skin cleansingbars comprising 0.5 to 20% silicone component which consists of siliconegum and silicone fluid in ratio of gum:fluid 10:1 to 1:10 wherein thesilicone component has particle size at least about 20 microns. Fattyacid soap, when used, is preferred at levels of 5-40%, 5-20% mostpreferred. These bars clearly, however, are mainly synthetic bars. Thisis in contrast to the primarily fatty acid soap bars of the inventionwhich would not normally be considered “mild” bars by the art. Thesubject invention concerns formulation of these normally not so mildbars with ingredients designed to impart lubricated, hydrated feel whilemaintaining creamy, dense foam.

[0012] Finally, JP 04/370,194 teaches transparent soap bars (i.e.,having visible light transmission, L%, greater than 40% in all examplesas measured using defined test) having fatty acid soap, a betaine groupcontaining siloxane compound and glycerin. Bars of the inventionpreferably do not contain betaine-containing siloxanes (preferably, theycontain standard silicones). Moreover, bars of the invention are opaquebars, having light transmittance of less than 40%,preferably less than30%, more preferably less than 20%, more preferably less than 15% andmost preferably less than 10%.

DESCRIPTION OF THE INVENTION

[0013] Due to the characteristics of surfactants present in conventionaltoilet soaps, although such soaps are extremely efficient cleansers ofskin, this high efficiency may leave the skin unprotected immediatelyafter the wash, thus provoking a stretched/dried out sensation.

[0014] In order to overcome this drawback, this present inventionprovides a new soap composition comprising fatty acid soap associatedwith mildness actives.

[0015] Laboratory tests have shown, surprisingly, that when siliconesand other emollient agents are mixed together, toilet soaps begin toprovide other benefits to the skin, over and above their cleansingqualities. These include the agreeable sensation of a lubricated,hydrated and a silky skin.

[0016] The results have been verified in internal evaluations done bysensory panelists.

[0017] Among the qualities of silicones which are applicable to theskin, the following may be highlighted: it is a hydrophobic substance,and thus water resistant, which remains after the rinsing process; it isa lubricant for the skin and hair. At the same time, it provides animproved tactile sensation and does not block the pores of skin.

[0018] These relevant features are optimized when the silicone iscombined with other emollient agents. The principal mechanism forobtaining this state is by adsorption of these emollient agents into thesilicone molecule.

[0019] Additionally, it was found that the soap composed in accordancewith this invention gives a more creamy denser foam, when compared withcurrent state of the art toilet soaps.

[0020] Thus, the present invention refers to a composition for soap,based on a conventional soap, with 60% to 90%, preferably 65% to 85% byweight of total fatty acids, to which are added from 0.1% to 15% byweight, of a combination of silicones and other emollients. To dry skin,this will give the sensation of soft, silky skin, to a greater extentthan other soaps.

[0021] More specifically the silicone should compare 0.01 to 7%,preferably 0.1 to 5%, more preferably 0.5 to 5% by wt. of composition; afirst emollient (glycerin, sorbitol and mixtures thereof) comprisesabout 0.1 to 5%, preferably 0.5 to 5% by wt. of composition and secondemollient comprises 0.1 to about 3% by wt. of composition.

[0022] Different types of silicones, such as linear, cyclic, substitutedsilicones and their combinations may be used in the present composition.Preferably, the silicone is a non-betaine containing silicone.

[0023] The emollients (e.g., second emollients) which are suitable fortoilet soap, under this invention, may be selected from polyols, fattyacids, vegetable, mineral and animal oils, and other emollients whichare similar or which may be adsorbed into the silicone chain.

[0024] Among the free fatty acids, babassu fatty acid and lauric acidare preferred.

[0025] From the vegetable oils, the sunflower oil, corn oil and almondoil among others may be used.

[0026] Glycerin and sorbitol (e.g., first emollient) are preferred amongthe polyols.

[0027] Bars of the invention also comprise about 5% to about 20%,preferably about 5% to 15% water.

[0028] The composition of the toilet soap bar, prepared in accordancewith this invention, may also include a certain percentage of anappropriate dye or colorant agent, added to the soap mix to impart thedesired color to the soap bar.

[0029] The quantities of perfume and coloring agent to be added to thesoap mix, prepared in accordance with this invention, are not critical,and should be such that they produce the desired coloring andaromatizing effect.

[0030] The bars of the invention are opaque bars. More specifically, ascompared to bars of JP 04/370,199 which have visible light transmissionL% of greater than 40% in all examples, bars of the invention have L% ofless than 40%, preferably less than 30%,preferably less than about 20%,more preferably less than about 15% and most preferably about 10% andbelow.

[0031] The L% value is that measured as described in JP 04/370,199. Morespecifically, a bar composition is cut into 2 cm thick test pieces, thesurface is smoothly polished and visible light transmittance L% of testpieces may be evaluated by a color difference meter (e.g., made byNippon Denshiki Company), color measurement, color difference meterND-2001 DP type.

[0032] Below, a novel soap composition according to the presentinvention is described by way of an example of how it should beprepared.

[0033] This example is merely illustrative and in no way limits thescope of this invention.

[0034] Unless stated otherwise, all percentages in specification andexample are intended to be by weight.

EXAMPLE

[0035] In this example, a cold-rolled soap method is used to prepare asoap bar.

[0036] A previously prepared soap mix for making a toilet soap cakeaccording to the present invention, composed of 65% to 85%, by weight,of salts of fatty acids, reckoned as total fatty acids, is placed in acrunching machine (Sigma, for example). The glycerine and/or polyols(first emollient), silicone and other emollients (second emollient) areadded in a proportion, by weight, of from 1% to 15%. The moisturecontents of the mix is then set at between 8% to 20%, by weight.

[0037] Finally, the desired amount of an appropriate coloring agent (forexample: Red Iragon PS paste and/or Orange Iragon II DC) is added,together with a desired amount of a soap compatible perfume, such asGemini 699.

[0038] During the whole process of adding these ingredients, thecomposition is thoroughly mixed with a suitable stirrer. Once the mix ishomogenous, the conventional stages of the process for obtaining soap ortoilet soap in cakes are carried out, these being: rolling (with aBuehler/Mazzoni Roller), compacting and extruding (using a Bonotextruder), cutting of the extruded bar and stamping and wrapping the bar(using a Sigma or Acmad Machine).

[0039] In this way, a cake of soap with a composition in accordance withthis invention and having the characteristics defined hereinabove areobtained.

1. An opaque soap bar composition comprising: (i) from about 0.01 toabout 7%, by weight, of silicone; (ii) from about 0.5% to about 5%, byweight, of a first emollient selected from the group consisting ofglycerin, sorbitol, and mixtures thereof; (iii) about 0.1 to about 5%,by weight, of a second emollient selected from the group consisting ofvegetable, animal or mineral oils, free fatty acids and mixturesthereof; (iv) about 60 to 90% by weight fatty acid soap; wherein saidbar has L% light transmittance under 40%.
 2. A soap bar composition asclaimed in claim 1 , wherein said silicone is selected from linear,cyclic, substituted silicones and mixtures thereof.
 3. A soap barcomposition according to claim 1 , wherein said free fatty acids areselected from babassu fatty acid or lauric acid.
 4. A soap barcomposition according to claim 1 , wherein said vegetable oil isselected from the group consisting of sunflower oil, corn oil, almondoil and mixtures thereof.
 5. A bar according to claim 1 , comprisingabout 0.1 to about 5% silicone.
 6. A bar according to claim 1 furthercomprising about 5% to 20% by wt. water.
 7. A bar according to claim 1 ,further comprising an effective amount of a dye and/or coloring agent.8. A composition according to claim 1 further comprising perfume.
 9. Acomposition according to claim 1 , where L% is 30% and below.